It is critical for the maintenance of proper health and fluid balance that an organism ingests an amount of salt appropriate to its needs. This ingestion is largely guided by taste cues. Without these cues, humans and other animals might ingest too much or too little salt which could result in health problems. There is growing evidence that salt taste transduction involves two pathways. Recent advances have begun to reveal the relative contributions of these two transduction pathways to taste-guided behaviors such as sodium recognition (under both sodium-depleted and sodium replete conditions), and also sodium and potassium detection and discrimination. However, significant questions remain. In particular, we do not know how these pathways contribute to the taste qualities of NaCl and other chloride salts. The proposed experiments will use psychophysical methods to test the discrimination, recognition and generalization of salt stimuli coupled with physiological manipulations such as nerve transections, sodium depletion, and epithelial sodium channel blocker administration to determine the contributions of these transduction pathways to taste-guided behavior. This project will extend our current knowledge of how interactions at the receptor level lead to taste perceptions and ultimately affect salt intake.